It is known to package chemical compositions, particularly those which may be of a hazardous or irritant nature, in water-soluble packages. Such packages may be made by folding or thermoforming one or more water-soluble films, as disclosed in WO 89/12587 and WO 92/17382, or may be formed by injection moulding a water-soluble composition, as disclosed in WO 01/36290.
Known injection moulded containers can contain one or two or more compositions. For example, WO 01/36290 discloses a water-soluble container having one or more compartments separated by vertical walls, the whole container being sealed by a single water-soluble film heat sealed over the opening of all of the compartments. A disadvantage of this arrangement is that it does not allow for the contents of the compartments to be delivered into a larger volume of water at different times. The film is the first part of the container to dissolve in water, leading to simultaneous opening of all of the compartments. Thus release of different compositions at different times is not possible.
WO 02/092456 and WO 02/085737 disclose a water-soluble container which can release different compositions at different times. The container comprises a member having at least two openings positioned on different sides if the member, each opening being closed by a film. By ensuring that the member is divided into at least two compartments and by ensuring that each compartment is closed by films having different dissolution properties from each other, it is possible to ensure that compositions are released at different times from each other when the container is placed in a large volume of water. A disadvantage of this arrangement is that the filling process is complex. One of the compartments is first filled through an uppermost opening with a composition and then sealed with a film. The container must then be turned over such that another opening is uppermost, and the process repeated using a second film. Such a process involves the manipulation of partially filled containers; turning them over leads to an increased risk of spillage as well as to increased production costs. It also involves the use of two different sealing films, again leading to increased complexity and costs. Furthermore the shape of the container is constrained by the requirement that it has at least two openings on different sides with flanges such that films can be sealed over the openings. Multiple flanges may lead to a product which is considered by consumers to be unattractive.